I went because of Saoirse Ronan. And she did not disappoint. Nor did her co-star. I knew nothing about the film. But it demanded concentration and it's twists and turns were challenging. Obviously the book which I had not read deserves credit for the originality of the subject. But the film deserves credit for making the subject reasonably accessible. Wonderful photography. So I would recommend it for its acting and the execution of the story line.